/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.dx.dex.file;

import com.android.dx.rop.cst.CstString;
import com.android.dx.util.AnnotatedOutput;
import com.android.dx.util.ByteArray;
import com.android.dx.util.Hex;
import com.android.dx.util.Leb128Utils;

/**
 * Representation of string data for a particular string, in a Dalvik file.
 */
public final class StringDataItem extends OffsettedItem {

	/** {@code non-null;} the string value */
	private final CstString value;

	/**
	 * Constructs an instance.
	 * 
	 * @param value
	 *            {@code non-null;} the string value
	 */
	public StringDataItem(CstString value) {
		super(1, writeSize(value));

		this.value = value;
	}

	/**
	 * Gets the write size for a given value.
	 * 
	 * @param value
	 *            {@code non-null;} the string value
	 * @return {@code >= 2}; the write size, in bytes
	 */
	private static int writeSize(CstString value) {
		int utf16Size = value.getUtf16Size();

		// The +1 is for the '\0' termination byte.
		return Leb128Utils.unsignedLeb128Size(utf16Size) + value.getUtf8Size()
				+ 1;
	}

	/** {@inheritDoc} */
	@Override
	public ItemType itemType() {
		return ItemType.TYPE_STRING_DATA_ITEM;
	}

	/** {@inheritDoc} */
	@Override
	public void addContents(DexFile file) {
		// Nothing to do here.
	}

	/** {@inheritDoc} */
	@Override
	public void writeTo0(DexFile file, AnnotatedOutput out) {
		ByteArray bytes = value.getBytes();
		int utf16Size = value.getUtf16Size();

		if (out.annotates()) {
			out.annotate(Leb128Utils.unsignedLeb128Size(utf16Size),
					"utf16_size: " + Hex.u4(utf16Size));
			out.annotate(bytes.size() + 1, value.toQuoted());
		}

		out.writeUleb128(utf16Size);
		out.write(bytes);
		out.writeByte(0);
	}

	/** {@inheritDoc} */
	@Override
	public String toHuman() {
		return value.toQuoted();
	}

	/** {@inheritDoc} */
	@Override
	protected int compareTo0(OffsettedItem other) {
		StringDataItem otherData = (StringDataItem) other;

		return value.compareTo(otherData.value);
	}
}
